1. Field of the Invention
The present invention relates to an optical connector which is used in interconnecting a pair of optical fibers or interconnecting an optical fiber and a photoelectric conversion element.
2. Description of the Related Art
An optical signal transmission path using optical fibers is generally laid by optically connecting the optical fibers by using optical connectors or the like at appropriate distances. As conventional optical connectors of this type, those described in, for example, Japanese Utility Model Unexamined Publication No. Sho. 61-126204 and Japanese Patent Examined Publication No. Hei. 8-7306 are known.
Namely, in the optical connector disclosed in Japanese Utility Model Unexamined Publication No. Sho. 61-126204, a housing for accommodating a pair of ferrules is split into upper and lower parts, and accommodating grooves for accommodating the ferrules and a pair of springs (compression coil springs) or the like are formed in the upper and lower parts of the split housing. In this structure, the upper and lower parts of such a housing are secured to each other by screwing down in a state in which the ferrules and the springs or the like are clamped from both upper and lower sides in the portion of the accommodating groove and are thereby prevented from coming off and are held.
On the other hand, the optical connector disclosed in Japanese Patent Examined Publication No. Hei. 8-7306 is provided with a plug body and a floating holder disposed floatably within the plug. A ferrule accommodating recess 102 and a holding-member fitting recess 103 are formed in this floating holder 101, as shown in FIG. 36.
Then, ferrules 105 and springs 106 which are fitted over distal end portions of optical fibers 104 are inserted into the ferrule accommodating recess 102 and the holding-member fitting recess 103 of the floating holder 101, and a ferrule pressing member 107 is inserted into the holding-member fitting recess 103. As a result of the insertion of this ferrule pressing member 107, retaining portions 107a of the ferrule pressing member 107 are engaged in retained portions 101a of the floating holder 101, and are thereby prevented from coming off and held.
At this time, the ferrules 105 are urged in the inserting direction, i.e., in the direction toward their distal ends, by the springs 106 which are in the compressed state.
In this structure, the floating holder 101 in the assembled state is accommodated in the aforementioned plug body of the type split into the upper and lower parts, and the upper and lower parts of the plug body are screwed down and are secured to each other.
However, in accordance with the above-described structure in which the housing or the plug body having the structure split into upper and lower parts is fixed by screwing down, there has been a drawback in that since the number of assembling steps increases, the assembling operation is time-consuming and troublesome. In addition, a screw and a nut are required, so that there is another problem in that the number of parts used increases.
Further, in accordance with the system disclosed in Japanese Patent Examined Publication No. Hei. 8-7306 in which the ferrule pressing member 107 is inserted into the holding-member fitting recess 103 in the direction in which the springs 106 are compressed, and the retaining portions 107a are engaged in the retained portions 110a, since the insertion is effected while compressing the springs 106, there has been a possibility that the components become disassembled due to the spring force during the assembly, making the assembly difficult. In addition, after the assembly, the spring force of the springs 106 set in the compressed state constantly acts on the ferrule pressing member 107 in the coming-off direction. Hence, there has been a possibility that if the optical connector is used over a long period of time, the engaging portions of the retaining portions 107a and the retained portions 110a become not longer able to withstand the load, resulting in spontaneous disassembly.
Also, the optical connector is provided with a protective boot, as necessary, for preventing damage to a portion of an optical fiber extending from the optical connector due to the bending or the like of such an extending portion depending on the laid condition and the like.
For example, as a structure for attaching a boot in an optical connector of this type, a structure in which the boot is attached by screwing down is known, as disclosed in U.S. Pat. No. 4,744,629. Also, a structure is known in which a retaining protrusion is provided along a peripheral edge portion of the boot, a fitting groove portion is provided in a corresponding connector housing, and the boot is attached by fitting and retaining the retaining protrusion in the fitting groove portion, as disclosed in Japanese Utility Model Unexamined Publication No. Sho. 61-126204.
However, in accordance with the above-described structure for attaching the boot by screwing down, attachment is troublesome, and there is a possibility of the boot from coming off due to the loosening of the screw. Further, in accordance with the attaching structure in which the boot-side retaining protrusion is fitted and retained in the connector housing-side fitting groove, a single thin-walled retaining protrusion is merely fitted in the fitting groove portion, so that there has been a drawback in that this structure is weak against a tensile force.